Pleat

A pleat (plait in older English) is a type of fold formed by doubling fabric back upon itself and securing it in place.

It is commonly used in clothing and upholstery to gather a wide piece of fabric to a narrower circumference.

[1] Pleats are categorized as pressed, that is, ironed or otherwise heat-set into a sharp crease, or unpressed, falling in soft rounded folds.

Cartridge pleats are used to gather a large amount of fabric into a small waistband or armscye without adding bulk to the seam.

Fabric is evenly gathered using two or more lengths of basting stitches, and the top of each pleat is whipstitched onto the waistband or armscye.

Linen chemises or smocks pleated with this technique have been found in the tenth century Viking graves in Birka.

The term is not contemporary, but is used by costume historians in reference to these styles as portrayed in the paintings of Antoine Watteau.

Shirts and blouses typically have pleats on the back to provide freedom of movement and on the arm where the sleeve tapers to meet the cuff.

Skirts, dresses and kilts can include pleats of various sorts to add fullness from the waist or hips, or at the hem, to allow freedom of movement or achieve design effects.

Utilitarian or very casual styles such as jeans and cargo pants are flat-front (without pleats at the waistband) but may have bellows pockets.

Today pleated blinds are popular all over the world due to their functionality, variety of design and effective protection from sunlight.